Over the last several years, a flurry of information has been distributed about mineral preparations and how much better they are than minerals in food. But there is no evidence these products are safe or better absorbed by the body. So stay away from high-priced supplements. Food is still the best possible source for most minerals.
A guideline for requirements is the dietary reference intake, or DRI. Many minerals do not yet have DRI designations, so included are the recommended dietary allowance (RDAs) in those cases.
* Boron: Found in fruits and vegetables, primarily apples, pears, broccoli, carrots. (No DRI)
* Calcium: Found in milk and milk products, dark-green leafy vegetables, broccoli, sardines and salmon eaten with bones, some tofu, fortified cereals. (DRI: 1,000 to 1,300 milligrams)
* Chloride: Found in table salt and fish. (No DRI)
* Chromium: Found in meat, whole grains, broccoli, brewer’s yeast, fortified cereal. (No DRI, but 50 to 200 micrograms estimated safe and adequate.)
* Copper: Found in shellfish, beans, nuts, seeds, organ meats, whole grains, potatoes. (No DRI, but 1.5 to 4 mg. estimated safe and adequate.)
* Fluoride: Fluoridated water and foods grown or cooked in it, marine fish (with bones), tea. (No DRI, but 1.5 to 4 mg. estimated safe and adequate.)
* Iodine: Iodized salt, seafood, seaweed, dairy products. (RDA 150 to 175 mcg.)
* Iron: Found in meat, poultry, fish, eggs, liver, kidneys, peas, beans, nuts, dried fruits, leafy green vegetables, enriched pasta and bread, fortified cereals. (RDA 15 to 30 mg.)
* Magnesium: Found in wheat bran, whole grains, leafy green vegetables, meat, milk, nuts, beans, bananas, apricots. (DRI 310 mg.)
* Manganese: Found in whole grains, nuts, vegetables, fruits, instant coffee, tea, cocoa powder, beans. (No RDA, but 2 to 5 mg. estimated safe and adequate.)
* Molybdenum: Found in whole grains, liver, beans, leafy vegetables. (No RDA, but 5 to 250 mcg. estimated safe and adequate.)
* Phosphorus: Found in fish, meat, poultry, dairy products, eggs, peas, beans, soft drinks, nuts. (DRI 700 to 1,250 mg.)
* Potassium: Found in oranges, orange juice, bananas, potatoes (with skin), dried fruits, yogurt, meat, poultry, milk. (No RDA, but 1,600 to 2,000 mg. estimated safe and adequate.)
* Selenium: Found in fish, shellfish, red meat, grains, eggs, chicken, garlic, organ meats and some vegetables, depending on the soil in which they were grown. Can be very toxic in large doses. (RDA 55 to 70 mcg.)
* Sodium: Found in table salt and prepared foods, especially cheese, smoked meats, prepared soups, salty snacks, fast food. (No RDA, but 2,400 mg. considered the maximum advisable intake.)
* Zinc: Found in meat, seafood, liver, eggs, brewer’s yeast, milk, beans, wheat germ. (RDA 12 to 15 mg.)
Dr. Sheldon Margen is a professor of public health at UC Berkeley; Dale A. Ogar is managing editor of the UC Berkeley Wellness Letter. Send questions to Dale Ogar, School of Public Health, UC Berkeley, Berkeley, CA 94720-7360, or e-mail to email@example.com. Eating Smart runs the second and fourth Mondays of the month.